MicroRNA are small RNA molecules about 22 nucleotides long that do not encode proteins. Their function is to change the expression of proteins by attaching to their mRNA. They participate in various biological processes and pathogenesis of many diseases, including cancer. MicroRNA-26a-5p (miR-26a-5p) takes part in developing many disease entities and may become a potential therapeutic agent.

The article aims to present the current knowledge on miR-26a-5p and consider the possible therapeutic use of this molecule.

State of knowledge:
Many studies on cell lines and model organisms indicate the suppressive function of miR-26a-5p in such neoplasms as breast cancer, pancreatic cancer, prostate cancer, thyroid cancer, or acute myeloid leukemia. In turn, in osteosarcoma cells, miR-26a-5p has an oncogenic character. miR-26a-5p is also associated with other diseases. Many authors have shown that this molecule is related to such entities as rheumatoid arthritis, osteoarthritis, preeclampsia, myocardial injury, or diabetic nephropathy.

Understanding the functions of miR-26a-5p and its participation in human diseases’ pathogenesis gives the possibility of the therapeutic use of this molecule in the future. However, knowledge of this subject is still limited. Further research to assess the efficacy and safety of the therapeutic use of miR-26a-5p is mandatory.

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